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Biological and morphological plasticity in polyphagous insect herbivores allow them to exploit diverse host plant species. Geographical differences in resource availability can lead to preferential host exploitation and result in inconsistent host specialization. Biological and molecular data provide insights into specialization and plasticity of such herbivore populations. In agricultural landscapes, Aphis gossypii encounters several crop and non-crop hosts, which exist in temporal and spatial proximity. We investigated the host-specialization of two A. gossypii host-associated populations (HAPs), which were field collected from cotton and squash (cotton-associated population and melon-associated population), and later maintained separately in the greenhouse. The two aphid populations were exposed to seven plant species (cotton, okra, watermelon, squash, cucumber, pigweed, and morning glory), and evaluated for their host utilization plasticity by estimating aphid's fitness parameters (nymphal period, adult period, fecundity, and intrinsic rate of increase). Four phenotypical characters (body length, head capsule width, hind tibia length and cornicle length) were also measured from the resulting 14 different HAP × host plant combinations. Phylogenetic analysis of mitochondrial COI sequences showed no genetic variation between the two HAPs. Fitness parameters indicated a significant variation between the two aphid populations, and the variation was influenced by host plants. The performance of melon-aphids was poor (up to 89% reduction in fecundity) on malvaceous hosts, cotton and okra. However, cotton-aphids performed better on cucurbitaceous hosts, squash and watermelon (up to 66% increased fecundity) compared with the natal host, cotton. Both HAPs were able to reproduce on two weed hosts. Cotton-aphids were smaller than melon-aphids irrespective of their host plants. Results from this study suggest that the two HAPs in the study area do not have strict host specialization; rather they exhibit plasticity in utilizing several hosts. In this scenario, it is unlikely that host-associated A. gossypii populations would evolve into host-specific biotypes.
Onion thrips, Thrips tabaci (Lindeman), is a prominent species infesting onion and tomato in the northern highlands of Tanzania. It causes considerable leaf damage by direct feeding and also transmits the Iris yellow spot virus (IYSV). Hence, one of the objectives of this study was to identify the most resistant onion entries against T. tabaci. One highly resistant (VI038552) and two resistant onion entries (VI038512 and AVON 1067) were identified against T. tabaci. Besides thrips resistance, the bulb size of VI038512 was also equivalent to one of the commercial varieties, Texas. The highly resistant VI038552 recorded the highest yield, followed by the resistant entry, VI038512. However, the yield of AVON 1067 was significantly lower. Elucidation of the biophysical bases of resistance revealed that there was a significant negative correlation between leaf angle as well as leaf toughness and thrips damage. The total epicuticular wax content in the leaves had a weak and non-significant negative relationship with thrips damage. The scanning electron microscopic study confirmed that the wax crystals occurred as filaments, rods, platelets, tubes and complex dendritic structures, and that they were densely arranged in resistant or moderately resistant entries. Studies on the biochemical basis of resistance confirmed that there was a significant negative relationship between total phenol content and thrips damage. Similarly, the relationship between total foliar amino acids or total sugars and thrips damage was inversely correlated and non-significant. Hence, entries VI038552 and VI038512 could be promising candidates for breeding programmes aimed at developing onion varieties that are resistant to thrips and that are high yielding, which will help to enhance the productivity of onions in sub-Saharan Africa.
The antimicrobial use (AU) option within the National Healthcare Safety Network summarizes antimicrobial prescribing data as a standardized antimicrobial administration ratio (SAAR). A hospital’s antimicrobial stewardship program found that greater involvement of an infectious disease physician in prospective audit and feedback procedures was associated with reductions in SAAR values across multiple antimicrobial categories.
Ferromagnetic/Ferroelectric/Ferromagnetic (Ni/PZT/Ni) tri-layer artificial multiferroelectric structures in spin capacitor configuration were fabricated by sputtering ferromagnetic electrodes on PZT. Magnetocapacitance, magnetoimpedance, and phase angle measurements were carried out by a wide range of frequencies and magnetic fields at room temperature. We also compared the magnetodielectric measurements with Ni/PZT/Ag and Ag/PZT/Ag tri-layers structures. Ni/PZT/Ni spin capacitor shows a significantly different behavior compared to conventional PZT capacitor with Ag electrode and mixed electrode capacitor with one ferromagnetic and one conventional electrode.
Pneumonia due to either Streptococcus pneumoniae (Sp) or Staphylococcus aureus (Sa) accounts for most mortality after influenza and acute respiratory illness (ARI). Because carriage precedes infection, we estimated Sp and Sa carriage to examine the co-colonization dynamics between Sp, Sa and respiratory viruses in the presence of ARI in the oropharynx. We tested oropharyngeal specimens of community subjects (aged ⩾2 years) with ARI for the presence of influenza A and B, 11 other common respiratory viruses, Sp and Sa, using real-time PCR. A total of 338 participants reported 519 ARI episodes of which 119 (35%) carried Sp, 52 (13%) carried Sa and 25 (7%) carried both. Thirty-five subjects tested positive for influenza, of which 14 (40%) carried Sp and six (17%) carried Sa, significantly more than in the influenza-negative group (P = 0·03 and P = 0·04, respectively). In subjects infected by any virus compared to those with no virus, Sp carriage (39·2% vs. 27·9%, P = 0·03) but not Sa carriage (11·6% vs. 14%, P = 0·6) was more frequent. For children, when Sa was present, Sp carriage tended to be less frequent than expected given the presence of viral infection, but not significantly [observed relative risk 1·14, 95% confidence interval (CI) 0·4–3·1; with a relative excess risk due to interaction of –0·11]. Independent of age, Sp carriers were more likely to return that season with subsequent ARI (odds ratio 2·14, 95% CI 1·1–4·3, P = 0·03). Both Sp and Sa carriage rates in the oropharynx increase during influenza infection in children. However, no negative interaction between Sp and Sa was observed. Sp carriers are more likely to suffer subsequent ARI episodes than non-carriers.
The likelihood of a patient attending regular follow up can affect decision making when planning and performing tympanomastoid surgery. This study investigated whether demographic factors were associated with loss to follow up.
A database of patients who had been investigated and treated for chronic otitis media was searched. Patients lost to follow up and a matching sample of patients who were formally discharged were identified. The demographic factors of age, sex and postcode were compared between the two groups. The information collected was also used to provide measures of deprivation.
Fifty patients in each group were identified. Patients lost to follow up were significantly younger than patients formally discharged (p < 0.02), and were more likely to live in an area of education and training deprivation (p < 0.05).
Younger patient age, and living in an area of education and training deprivation, are associated with a higher incidence of loss to follow up.
The aim of this study was to identify and develop entomopathogenic fungi as biopesticides for management of Maruca vitrata (Fabricius). Fourteen isolates of Metarhizium anisopliae (Metchnikoff) Sorokin and six of Beauveria bassiana (Bals.-Criv.) Vuill. were screened against first instar larvae of M. vitrata. The two most virulent isolates were selected and further tested for production in four liquid media. Different formulations of one isolate were evaluated against different developmental stages. Metarhizium anisopliae ICIPE 18 and ICIPE 69 caused highest larval mortality of 91 and 81%, with lethal time to 50% mortality (LT50) values of 1.8 and 1.7 days and LC50 of 1.07 × 107 and 3.01 × 106conidia/ml, respectively. ICIPE 69 yielded more biomass and propagules in two liquid media than ICIPE 18. All developmental stages and adult moths were susceptible to fungal infection and horizontal transmission caused a significant reduction in fecundity. Isolate ICIPE 69 was identified as the most potent isolate for managing M. vitrata based on demonstrated efficacy against different developmental stages and amenability to production in liquid media and could be utilized as an alternative to pesticides in cowpea IPM.
Shape memory alloys (SMAs) exist in different phases depending on temperature and stress level. Experimental evidence shows that SMAs oscillate between two shapes during thermal cycling. This phenomenon, known as two-way shape-memory effect, occurs due to a transformation between the austenitic phase and the martensitic phase. The two-way shape-memory behavior is studied here by molecular dynamics simulations in NiTi nanowires of different diameter to understand the effect of loading on the size-dependent behavior. Thermal cycling is performed while holding the system at zero stress and at a fixed compressive stress. At zero stress, the martensite structure formed on cooling depends on the wire diameter. However, when cooling is performed at a sufficiently large constant compressive stress, the formation of a single martensitic variant is observed for all diameters.
To analyse trends in two-week rule referrals for head and neck cancer over 10 years.
Data from two-week referrals received by the Wirral University Hospital NHS Trust between 1 January and 30 June 2012 were compared with similar data from 2002.
A total of 357 referrals were received during the 6-month audit period, compared with 149 during the whole of 2002. Cancer pick-up rates were 9 per cent and 5 per cent in the first and second cycles, respectively.
The annual number of two-week referrals made to our department increased by over 450 per cent in 10 years, but the resulting cancer pick-up rate fell by nearly 50 per cent. Whilst cancer patients need to be seen quickly, the current system is inefficient in parts. Modifications to the treatment pathway should be considered to improve patient care quality and reduce pressure on ENT departments.
Maruca vitrata Fabricius (legume pod borer, LPB), the most serious economic pest of legume crops in the tropics, is primarily controlled by chemical pesticide application with serious consequences for the ecosystem and human health. In this study, various concentrations of three commercial biopesticides, NeemBaan®, Bactospeine® (Bacillusthuringiensis (Bt) subsp. kurstaki) and Florbac® (Btaizawai), were tested either in the field or laboratory or in both conditions. In the laboratory experiments, different concentrations of NeemBaan® exhibited significant effects on the mortality of all the tested larval instars and a mortality rate of over 80% was recorded at a dose of 3000 ppm. Bactospeine® was found to be more effective against M. vitrata than Florbac®. Bactospeine® applied at a lower dose of 500 ppm caused 100% mortality in the first-instar and second-instar larvae; however, at the same dose, Florbac® caused mortality of only 26.67% (first instar) and 20% (second instar). In the field experiments, a higher dose of NeemBaan® (6000 ppm) significantly reduced pod damage to approximately 20% in both the first and second cropping seasons. In conclusion, neem- and Bt-based biopesticide products have insecticidal potential to be used in an integrated pest management strategy for controlling M. vitrata in Thailand.
To describe antimicrobial resistance patterns for healthcare-associated infections (HAIs) reported to the National Healthcare Safety Network (NHSN) during 2009-2010.
Central line-associated bloodstream infections, catheter-associated urinary tract infections, ventilator-associated pneumonia, and surgical site infections were included. Pooled mean proportions of isolates interpreted as resistant (or, in some cases, nonsusceptible) to selected antimicrobial agents were calculated by type of HAI and compared to historical data.
Overall, 2,039 hospitals reported 1 or more HAIs; 1,749 (86%) were general acute care hospitals, and 1,143 (56%) had fewer than 200 beds. There were 69,475 HAIs and 81,139 pathogens reported. Eight pathogen groups accounted for about 80% of reported pathogens: Staphylococcus aureus (16%), Enterococcus spp. (14%), Escherichia coli (12%), coagulase-negative staphylococci (11%), Candida spp. (9%), Klebsiella pneumoniae (and Klebsiella oxytoca; 8%), Pseudomonas aeruginosa (8%), and Enterobacter spp. (5%). The percentage of resistance was similar to that reported in the previous 2-year period, with a slight decrease in the percentage of S. aureus resistant to oxacillins (MRSA). Nearly 20% of pathogens reported from all HAIs were the following multidrug-resistant phenotypes: MRSA (8.5%); vancomycin-resistant Enterococcus (3%); extended-spectrum cephalosporin-resistant K. pneumoniae and K. oxytoca (2%), E. coli (2%), and Enterobacter spp. (2%); and carbapenem-resistant P. aeruginosa (2%), K. pneumoniae/oxytoca (<1%), E, coli (<1%), and Enterobacter spp. (<1%). Among facilities reporting HAIs with 1 of the above gram-negative bacteria, 20%-40% reported at least 1 with the resistant phenotype.
While the proportion of resistant isolates did not substantially change from that in the previous 2 years, multidrug-resistant gram-negative phenotypes were reported from a moderate proportion of facilities.
We provide a criterion for the central norm to be any value in the simple continued fraction expansion of
for any non-square integer
. We also provide a simple criterion for the solvability of the Pell equation
in terms of congruence conditions modulo
Because of its strong association (r 0·85) with percentage of body fat determined by dual-energy X-ray absorptiometry, hip circumference divided by height1·5 (the body adiposity index) has recently been proposed as an index of body fatness among adults. We examined whether this proposed index was more strongly associated with skinfold thicknesses and levels of CVD risk factors (lipids, fasting insulin and glucose, and blood pressure) than was BMI among 2369 18- to 49-year-olds in the Bogalusa Heart Study. All analyses indicated that the body adiposity index was less strongly associated with skinfold thicknesses and CVD risk factors than was either waist circumference or BMI. Correlations with the skinfold sum, for example, were r 0·81 (BMI) v.r 0·75 (body adiposity index) among men, and r 0·87 (BMI) v.r 0·80 among women; P< 0·001 for both differences. An overall index of seven CVD risk factors was also more strongly associated with BMI (r 0·58) and waist circumference (r 0·61) than with the body adiposity index (r 0·49). The weaker associations with the body adiposity index were observed in analyses stratified by sex, race, age and year of examination. Multivariable analyses indicated that if either BMI or waist circumference were known, the body adiposity index provided no additional information on skinfold thicknesses or risk factor levels. These findings indicate that the body adiposity index is likely to be an inferior index of adiposity than is either BMI or waist circumference.
Over the past 2 decades, multiple interventions have been developed to prevent catheter-associated urinary tract infections (CAUTIs). The CAUTI prevention guidelines of the Healthcare Infection Control Practices Advisory Committee were recently revised.
To examine changes in rates of CAUTI events in adult intensive care units (ICUs) in the United States from 1990 through 2007.
Data were reported to the Centers for Disease Control and Prevention (CDC) through the National Nosocomial Infections Surveillance System from 1990 through 2004 and the National Healthcare Safety Network from 2006 through 2007. Infection preventionists in participating hospitals used standard methods to identify all CAUTI events (categorized as symptomatic urinary tract infection [SUTI] or asymptomatic bacteriuria [ASB]) and urinary catheter–days (UC-days) in months selected for surveillance. Data from all facilities were aggregated to calculate pooled mean annual SUTI and ASB rates (in events per 1,000 UC-days) by ICU type. Poisson regression was used to estimate percent changes in rates over time.
Overall, 36,282 SUTIs and 22,973 ASB episodes were reported from 367 facilities representing 1,223 adult ICUs, including combined medical/surgical (505), medical (212), surgical (224), coronary (173), and cardiothoracic (109) ICUs. All ICU types experienced significant declines of 19%–67% in SUTI rates and 29%–72% in ASB rates from 1990 through 2007. Between 2000 and 2007, significant reductions in SUTI rates occurred in all ICU types except cardiothoracic ICUs.
Since 1990, CAUTI rates have declined significantly in all major adult ICU types in facilities reporting to the CDC. Further efforts are needed to assess prevention strategies that might have led to these decreases and to implement new CAUTI prevention guidelines.
In May 2009, we investigated a hospital outbreak of pandemic H1N1 (pH1N1) infection among healthcare personnel (HCP). Thirteen (65%) of 20 HCP with pH1N1 infection had healthcare-associated cases, which were primarily attributed to transmission among HCP. Eleven (55%) of HCP with pH1N1 infection worked for 1 day or more after the onset of illness. Personnel working with mild illness may have contributed to transmission among HCP.
Finger millet (Eleusine coracana) is extensively cultivated and consumed in India and Africa. The millet seed coat is a rich source of dietary fibre and phenolic compounds. The effect of feeding a diet containing 20 % finger millet seed coat matter (SCM) was examined in streptozotocin-induced diabetic rats. Diabetic rats maintained on the millet SCM diet (diabetic experimental (DE) group) for 6 weeks exhibited a lesser degree of fasting hyperglycaemia and partial reversal of abnormalities in serum albumin, urea and creatinine compared with the diabetic control (DC) group. The DE group of rats excreted comparatively lesser amounts of glucose, protein, urea and creatinine and was accompanied by improved body weights compared with their corresponding controls. Hypercholesterolaemia and hypertriacylglycerolaemia associated with diabetes were also notably reversed in the DE group. Slit lamp examination of the eye lens revealed an immature subcapsular cataract with mild lenticular opacity in the DE group of rats compared to the mature cataract with significant lenticular opacity and corneal vascularisation in the DC group. Lower activity of lens aldose reductase, serum advanced glycation end products and blood glycosylated Hb levels were observed in the DE group. The millet SCM feeding showed pronounced ameliorating effects on kidney pathology as reflected by near normal glomerular and tubular structures and lower glomerular filtration rate compared with the shrunken glomerulus, tubular vacuolations in the DC group. Thus, the present animal study evidenced the hypoglycaemic, hypocholesterolaemic, nephroprotective and anti-cataractogenic properties of finger millet SCM, suggesting its utility as a functional ingredient in diets for diabetics.